No callbacks. No lifecycle diagrams. You don't give up control of the event loop. No memory management. You can add new widgets by copying/ pasting/modifying

No callbacks. No lifecycle diagrams. You don't give up control of the event loop. No memory management. You can add new widgets by copying/ pasting/modifying from demos easily. Lisp is interesting in that unevaluated code is a data structure of the language. In immediate mode GUIs, the sequence of function calls is your data structure.